The proposed research concerns the elucidation of regulatory mechanisms involved in the process of mitochondrial energy generation in liver. Two general approaches have been selected for use: a) to investigate the effect of various small molecular weight species, i.e., adenine and guanine nucleotides, long chain acyl CoA derivatives and other similar types of physiological species, and b) to investigate the effect of various divalent metal cations on various metabolic processes. The primary enzymatic functions currently being investigated are the pyruvate, alpha-ketoglutarate and glutamate dehydrogenase reactions and the phosphoenolpyruvate carboxykinase reactions. Divalent metal cation translocation is being studied using the fluorescent divalent metal cation chelate probe chlorotetracycline in combination with various other more classical techniques for assessing metal cation translocation. Studies are being performed in perfused liver, isolated hepatocytes and isolated mitochondrial systems. BIBLIOGRAPHIC REFERENCE: Luthra, R. and Olson, M.S., Studies of Mitochondrial Calcium Movements using Chlorotetracycline. Biochim. Biophys. Acta 440 (1976) 744-758.